Features HIGH OVERLOAD CAPACITY: Digital amplifier has a higher overload capacity than analog amplifier, and Digital Dual Channel Amplifier Module won't cause crossover distortion, transient inter modulation distortion and you don't have to worry about the loudspeaker internal resistance. DUAL CHANNEL: Integrated amp uses NE5532 pre-amp, and TDA7492 chip for dual channel of 50W+50W power output. USED FOR: Amplifier Board is applicable speaker impedance are 4, 6, 8ohm, great for turning normal speaker into Bluetooth speaker. SUPPORTS BLUETOOTH V4.0: Stereo AMP Board supports Bluetooth V4.0 audio input and DC 8V to 25V voltage input. GOOD SOUND QUALITY: Sound quality is very good by using this audio power amplifier module. Description: This is an audio power amplifier board that strengthens low-power, inaudible electronic audio signals such as the signal from radio receiver or electric guitar pickup to a level that is strong enough for driving loudspeakers or headphones. Power amplifiers make the signal audible to listeners. It is the final electronic stage in a typical audio playback chain before the signal is sent to the loudspeakers and speaker enclosures. Specifications: Chip: TDA7492 Audio Input: Bluetooth V4.0 Output Power: 2x50W Suitable Speaker Impedance: 4ohm, 6ohm, 8ohm Input Voltage: 8V~25V DC(2.1mm jack) Size: 84 x 50mm / 3.3 x 1.97" Package Includes: 1 x Amplifier Board Package List 1 x Variable Frequency Drive